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Nuclei-rich galvanizing strategy for suppressing zinc dendrite growth

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Rare Metals 2024年第8期43卷 4016-4018页

作者： Hai-Xia Wu kai-lu Guo College of Chemistry and Chemical Engineering Henan Key Laboratory of Function-Oriented Porous MaterialsLuoyang Normal UniversityLuoyang 471934China

The uncontrolled growth of zinc dendrites on zinc anode hinders the application of zinc ion *** solve this problem,lu's group proposed a nuclei-rich galvanizing strategy for suppressing the zinc dendrite *** allows the nuclei-rich zinc electrode to cycle steadily for1200 h and have a high Coulombic efficiency of 99.7%at15 mA·cm^(-2)with a deposited amount of 10 mAh·cm^(-2).Moreover,the Zn-MnO_(2) battery with a low N/P ratio of 1.9exhibited sustained cycling life.

关键词： cycling sustained battery

QSobel:A novel quantum image edge extraction algorithm

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Science China(Information Sciences) 2015年第1期58卷 107-119页

作者： ZHANG Yi lu kai GAO YingHui Science and Technology on Parallel and Distributed Processing Laboratory National University of Defense Technology College of Computer National University of Defense Technology College of Electronic Science and Engineering National University of Defense Technology

Edge extraction is an indispensable task in digital image processing. With the sharp increase in the image data, real-time problem has become a limitation of the state of the art of edge extraction *** this paper, QSobel, a novel quantum image edge extraction algorithm is designed based on the flexible representation of quantum image(FRQI) and the famous edge extraction algorithm Sobel. Because FRQI utilizes the superposition state of qubit sequence to store all the pixels of an image, QSobel can calculate the Sobel gradients of the image intensity of all the pixels simultaneously. It is the main reason that QSobel can extract edges quite fast. Through designing and analyzing the quantum circuit of QSobel, we demonstrate that QSobel can extract edges in the computational complexity of O(n2) for a FRQI quantum image with a size of2 n × 2n. Compared with all the classical edge extraction algorithms and the existing quantum edge extraction algorithms, QSobel can utilize quantum parallel computation to reach a significant and exponential ***, QSobel would resolve the real-time problem of image edge extraction.

关键词： edge extraction quantum image processing FRQI Sobel computational complexity

Surveying concurrency bug detectors based on types of detected bugs

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Science China(Information Sciences) 2017年第3期60卷 5-31页

作者： Zhendong WU kai lu Xiaoping WANG Science and Technology on Parallel and Distributed Processing Laboratory National University of Defense Technology College of Computer National University of Defense Technology

Concurrency bugs widely exist in concurrent programs and have caused severe failures in the real world. Researchers have made significant progress in detecting concurrency bugs, which improves software reliability. In this paper, we survey the most up-to-date and well-known concurrency bug detectors. We categorize the existing detectors based on the types of concurrency bugs. Consequently, we analyze data race detectors, atomicity violation detectors, order violation detectors, and deadlock detectors, respectively. We also discuss some other techniques which are mostly related to concurrency bug detection, including schedule bounding techniques, interleaving optimizing techniques, path expanding techniques, and deterministic replay techniques. Additionally, we statistically analyze the reviewed detectors and get some interesting findings, for instance, nearly 86% of previous detectors focus on data races and atomicity violations, and dynamic approaches are popular(74%). We also discuss the limitations of previous detectors, finding that 91% of previous detectors suffer from false negatives and 64% of previous detectors suffer from runtime overhead. Based on the reviewed detectors and statistical analysis, we conclude some future research directions, including accuracy, performance,applicability, and integrality.

关键词： concurrency bug detection data race atomicity violation order violation deadlock

Zeolite polymer membrane as protective interface for Mg battery

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Rare Metals 2024年第9期43卷 4636-4638页

作者： Hai-Xia Wu kai-lu Guo College of Chemistry and Chemical Engineering Henan Key Laboratory of Function-Oriented Porous MaterialsLuoyang Normal UniversityLuoyang 471934China

Excessive electrolyte decomposition seriously determines the performance of high-voltage Mg batteries. In Nazar's work, the strategy using a zeolite polymer membrane as a protective interface was proposed to restrain the electrolyte decomposition. This strategy could boost Mg plating/stripping performance up to 6000 h in zeolite/Mg|zeolite/Mg symmetric cells and 91%capacity retention in zeolite/Mg||Mo_(3)S_(4)battery after 200 *** storage devices have been intensively explored because of their important roles in our daily lives [1D3].

关键词： zeolite interface electrolyte

Study on constant-pressure specific heat of non-equilibrium phase change process in gas-liquid two-phase flow system

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Chinese Science Bulletin 2007年第22期52卷 3162-3167页

作者： XU kai lu WenQiang College of Physical Sciences Graduate University of the Chinese Academy of Sciences Beijing 100049 China

In this paper,the air-water vapor-water system is taken as an example,and the formula of constant-pressure specific heat during non-equilibrium phase change process in the two-phase flow system is deduced using the theory of two-phase flow and thermophysics. The constant-pressure specific heat of non-equilibrium phase change process is calculated with the corresponding numerical model,and the numerical results are compared to those of the equilibrium phase change process. It is shown that in evaporation process,the variational rate of the non-equilibrium specific heat increases with increasing initial fluid temperature and particle mass fraction. The smaller particle radius is,the faster the varia-tional rate is. Meanwhile,the constant-pressure specific heat of equilibrium process is higher than that of the non-equilibrium process all the time.

关键词：平衡相空气水汽热物理学

Random Forest-Based Fatigue Reliability-Based Design Optimization for Aeroengine Structures

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 665-684页

作者： Xue-Qin Li lu-kai Song School of Energy and Power Engineering Beihang UniversityBeijing100191China Department of Mechanical Engineering The Hong Kong Polytechnic UniversityKowloonHong Kong999077China Research Institute of Aero-Engine Beihang UniversityBeijing100191China

Fatigue reliability-based design optimization of aeroengine structures involves multiple repeated calculations of reliability degree and large-scale calls of implicit high-nonlinearity limit state function,leading to the traditional direct Monte Claro and surrogate methods prone to unacceptable computing efficiency and *** this case,by fusing the random subspace strategy and weight allocation technology into bagging ensemble theory,a random forest(RF)model is presented to enhance the computing efficiency of reliability degree;moreover,by embedding the RF model into multilevel optimization model,an efficient RF-assisted fatigue reliability-based design optimization framework is *** the low-cycle fatigue reliability-based design optimization of aeroengine turbine disc as a case,the effectiveness of the presented framework is *** reliabilitybased design optimization results exhibit that the proposed framework holds high computing accuracy and computing *** current efforts shed a light on the theory/method development of reliability-based design optimization of complex engineering structures.

关键词： Random forest reliability-based design optimization ensemble learning machine learning

DFTracker: detecting double-fetch bugs by multi-taint parallel tracking

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Frontiers of Computer Science 2019年第2期13卷 247-263页

作者： Pengfei WANG kai lu Gen LI Xu ZHOU Science and Technology on Parallel and Distributed Processing Laboratory National University of Defense Technology Changsha 410073 China College of Computer National University of Defense Technology Changsha 410073 China Collaborative Innovation Center of High Performance Computing National University of Defense Technology Changsha 410073 China

A race condition is a common trigger for concurrency bugs. As a special case, a race condition can also occur across the kernel and user space causing a doublefetch bug, which is a field that has received little research attention. In our work, we first analyzed real-world doublefetch bug cases and extracted two specific patterns for doublefetch bugs. Based on these patter ns, we proposed an approach of multi-taint parallel tracking to detect double-fetch bugs. We also implemented a prototype called DFTracker (doublefetch bug tracker), and we evaluated it with our test suite. Our experiments demonstrated that it could effectively find all the double-fetch bugs in the test suite including eight realworld cases with no false negatives and minor false positives. In addition, we tested it on Linux kernel and found a new double-fetch bug. The execution overhead is approximately 2x for single-file cases and approximately 9x for the whole kernel test, which is acceptable. To the best of the authors1 knowledge, this work is the first to introduce multi-taint parallel tracking to double-fetch bug detection—an innovative method that is specific to double-fetch bug features—and has better path coverage as well as lower runtime overhead than the widely used dynamic approaches.

关键词： multi-taint parallel tracking double fetch race condition between kernel and user time of check to time of use real-world case analysis Clang Static Analyzer

Untrusted Hardware Causes Double-Fetch Problems in the I/O Memory

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Journal of Computer Science & Technology 2018年第3期33卷 587-602页

作者： kai lu Peng-Fei Wang Gen Li Xu Zhou College of Computer National University of Defense Technology Changsha 410073 China Science and Technology on Parallel and Distributed Processing Laboratory National University of Defense Technology Changsha 410073 China Collaborative Innovation Center of High-Performance Computing National University of Defense Technology Changsha 410073 China

The double fetch problem occurs when the data is maliciously changed between two kernel reads of the supposedly same data, which can cause serious security problems in the kernel. Previous research focused on the double fetches between the kernel and user applications. In this paper, we present the first dedicated study of the double fetch problem between the kernel and peripheral devices （aka. the hardware double fetch）. Operating systems communicate with peripheral devices by reading from and writing to the device mapped I/O （input and output） memory. Owing to the lack of effective validation of the attached hardware, compromised hardware could flip the data between two reads of the same I/O memory address, causing a double fetch problem. We propose a static pattern-matching approach to identify the hardware double fetches from the Linux kernel. Our approach can analyze the entire kernel without relying on the corresponding hardware. The results are categorized and each category is analyzed using case studies to discuss the possibility of causing bugs. We also find four previously unknown double-fetch vulnerabilities, which have been confirmed and fixed after reporting them to the maintainers.

关键词： hardware double fetch double-fetch bug I/O memory peripheral device double-fetch vulnerability

Fouling characteristics of 90° elbow in high salinity wastewater from coal chemical industry

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Chinese Journal of Chemical Engineering 2021年第7期34卷 143-151页

作者： Yang Lü kai lu Youxiang Bai Yulong Ma Yongsheng Ren State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering Department of Chemistry&Chemical EngineeringNational Demonstration Center for Experimental Chemistry EducationNingxia University

Due to the high salt content of coal chemical wastewater,pipeline fouling often occurs during wastewater *** will cause the diameter of the pipe to shrink or even block,which is not conducive to the safe and stable operation of the wastewater treatment *** this paper,the experimental device was designed by using FluENT software and the fouling deposition mechanisms at different flow velocities and different positions in a 90 deg bend were *** experimental results show that when the flow velocity is between 0.2 m·s^(-1) and 0.3 m·s^(-1),the thickness of fouling layer was positively correlated with the flow velocity;when the flow velocity is equal to 0.4 m·s^(-1),the formation of fouling is the most serious;when the flow velocity is between 0.4 m·s^(-1) and 0.7 m·s^(-1),the thickness of fouling layer was negative correlation with the flow velocity;with the increase of inlet velocity,the time for sediment point to develop into sediment surface is *** fouling layer is easy to fall off because of the large shear force on the wall surface of the inner bend of the 90°elbow,so the density of sediment at this position is high.

关键词： Fouling Waste water CFD Inlet velocity